This invention relates to recycling apparatus for obtaining oil from waste plastics.
Conventional apparatus to obtain heavy oil (fuel oil or its equivalent) from waste plastics (high-polymeric waste) involves thermal decomposition.
This type of conventional apparatus melts solid waste plastics such as polyethylene, polyester and vinyl chloride at the relatively low temperature of approximately 250.degree. C. (or 70.degree. C. for vinyl chloride) in a melting tank, resulting in thermal decomposition of the molten waste plastics in a thermal decomposition tank heated to approximately 400.degree. C. (or 170.degree. C. for vinyl chloride). The desired heavy oil is obtained by cooling the gas produced by the thermal decomposition.
If solid waste plastics are directly charged to the thermal decomposition tank, the waste plastics will become carbonized. This carbonization lowers recycling efficiency, and the product of carbonization is not easy to dispose of. This is the reason why a melting tank is required to first melt the solid waste plastic.
However, conventional apparatuses of the type just mentioned have involved a number of problems.
First, the need for the melting tank in addition to the thermal decomposition tank makes the whole assembly more intricate, larger, more costly and difficult to maintain.
Second, the longer time required for the processing of waste plastics lowers the productivity and increases the production cost of heavy oil.
This invention solves the aforementioned problems with the conventional technologies. The object of this invention is to provide simple and compact recycling apparatus for obtaining oil from waste plastics resulting in substantial cost savings and ease of maintenance while offering higher productivity and greater economy.